Cold Rolling Mill Of Small-scale Three-roll Planetary Research And Development

Along with the fast development of the enormous building market of our country, the demand of stick steel is further increased. However, the stick steels is mainly gained by drawing and hot rolling currently. There are many problems which aren't effectively solved, such as the high production cost, products surface quality that is not easy to get assurance and environmental pollution that caused by hot rolling, etc. So there is much important real meaning to research and develop the 3-Roller Planet Schrage Waltwerk(PSW),which is suitable to produce stick steels.This paper briefly introduces its appearance development, transmission principles and the advantages and disadvantages of the 3-Roller PSW. On the basis of summarizing forefathers' research results of designing PSW, the author have done movement analysis of the PSW and has tentatively probed calculation of the rotation speed of the roller and rolling pace of workpiece.Three rollers of the PSW are fixed 120° each other in space, and the roller axes and the rolling center line have an oblique angle α and drift angle β . When the PSW rolls workpiece, three rollersrotate by their own axes respectively, while rollers revolve round the workpiece. For such a structural character of PSW and planetary movement relation, it becomes very difficult to gain accuracy rolling speed. In order to effectively solve this problem, this paper uses the meshing principle, through varying the appropriate coordinate, and programs on the basis of Visual Basic programming platform. It analyses the contour of rollers and workpiece, and contact line. The author draws the curve of rolling speed by decompounding the rolling velocity and obtained the qualification that meets the workpiece not rolling when the 3-roller rolls.Through changing the initial design parameter in the procedure, we can get different workpiece size and corresponding rolling mill structure and performance parameter curves.In additional, in the two different situations of considering and not considering the elasticity of rollers, this paper theoretically derives calculation method of contact line. Based on, it also has derived the solving of rolling pressure, rolling torque and rolling power, then estimated the efficiency of the rolling mill, and selected the suitable electromotor. By the primary design of the PSW, it gains the structure size of rollers and installation location parameters, and acquires the size of workpiece, rolling quantity, rolling precision, rolling speed and other important data. It is identical with reality rolling curve and theory curve, so it indicates that both the theory derive curve and programming calculation are precise. And it offers reliable technology support and theory foundation for research and developing more 3-roller PSW afterwards.